A working device conventionally used for trimming branches at high elevations has a working, section of a pole saw, etc. on the end of an extendible rod section and a drive section on the rear end of the rod section (See Patent Literatures 1 and 2). Various kinds of such working devices are available for kinds of operations. In the structure of such a working device, working sections and drive sections are optionally selected and replaced on a rod section according to the kind of operation.